PSK-Type Modulation with Overlapping Baseband Pulses

One of the most interesting challenges in the field of digital radio is to generate and transmit signals which meet the spectral requirements and which have high detection efficiencies. The spectral efficiency of PSK-type modulation with overlapping baseband pulses is known to be better than that with nonoverlapping pulses of the same form; but, to our knowledge, no analysis is presently available to determine their detection efficiency. In this paper a method has been given to evaluate the error probability performance of PSK-type modulation with baseband pulses of finite overlap and mutually independent samples. It is shown that the error probability can be computed with any desired accuracy. For BPSK and for some typical transmit and receive filters and for a transparent channel corrupted by additive Gaussian noise we compare the detection efficiencies when the baseband modulation pulses have zero and nonzero overlap and when the transmitted signal satisfies the same spectral requirement. The nonoverlapping rectangular signaling is shown to be superior to overlapping raised-cosine signaling, but the differential degradation is less than 0.8 dB if the twosided 99-percent bandwidth W99satisfies . The analytical results presented here for a binary system can be extended with minor modifications to any -ary PSK system, .